OBJECTIVES: 1) A bacteriophage vector for recombinant DNA work with the genotype lambda gt Aam Lam Oam. Lambda B has been prepared and its enhanced biological containment will be determined using a cloned plasmid fragment coding for kanamycin resistance as a marker. 2) The use of lambda gt Oam29.lambda C as a selective tool in cloning origins of replication or proteins involved in DNA replication (O gene product) will be evaluated. 3) The binding of ethidium to lambda DNA condensed in phage heads will be analyzed flurometrically. 4) The effects of diamines and polyamines on the binding of ethidium to free and packaged DNA will be examined. 5) The bulk isolation and separation of mouse metaphase chromosomes from teratocarcinoma cell lines will be undertaken.